Why do you choose to focus on him, what things he has and what he is doing? What does this provide for you? What needs are you fulfilling by putting your focus on him rather than yourself?
He is your X for some very good reasons.
Do you compare the quality of your life to those around you to decide whether you are in a good place? Can you try to change to focus to yourself and decide whether you and you alone are happy with the way your life is headed? Can you cut the ties to your X and put the focus back on yourself without comparisons?
I find that minding my side of the street is much more productive and healing. I do not rate my level of satisfaction based on where anyone else is or what they have. I find it much easier to maintain my serenity and growth by keeping my focus on me.